Introduce helper macro for_each_cmsghdr as a wrapper of the enumerating
cmsghdr from msghdr, just cleanup.
Signed-off-by: Gu Zheng <[email protected]>
---
v2: use the lower-case macro name as Joe suggested.
---
.../networking/timestamping/timestamping.c | 4 +---
.../networking/timestamping/txtimestamp.c | 4 +---
crypto/af_alg.c | 2 +-
include/linux/socket.h | 4 ++++
net/core/scm.c | 3 +--
net/dccp/proto.c | 5 ++---
net/ipv4/ip_sockglue.c | 2 +-
net/ipv6/datagram.c | 2 +-
net/iucv/af_iucv.c | 4 +---
net/rds/send.c | 4 ++--
net/rxrpc/ar-output.c | 2 +-
net/sctp/socket.c | 3 +--
12 files changed, 17 insertions(+), 22 deletions(-)
diff --git a/Documentation/networking/timestamping/timestamping.c b/Documentation/networking/timestamping/timestamping.c
index 5cdfd74..3106e88 100644
--- a/Documentation/networking/timestamping/timestamping.c
+++ b/Documentation/networking/timestamping/timestamping.c
@@ -169,9 +169,7 @@ static void printpacket(struct msghdr *msg, int res,
res,
inet_ntoa(from_addr->sin_addr),
msg->msg_controllen);
- for (cmsg = CMSG_FIRSTHDR(msg);
- cmsg;
- cmsg = CMSG_NXTHDR(msg, cmsg)) {
+ for_each_cmsghdr(cmsg, msg) {
printf(" cmsg len %zu: ", cmsg->cmsg_len);
switch (cmsg->cmsg_level) {
case SOL_SOCKET:
diff --git a/Documentation/networking/timestamping/txtimestamp.c b/Documentation/networking/timestamping/txtimestamp.c
index b32fc2a..e44ef35 100644
--- a/Documentation/networking/timestamping/txtimestamp.c
+++ b/Documentation/networking/timestamping/txtimestamp.c
@@ -149,9 +149,7 @@ static void __recv_errmsg_cmsg(struct msghdr *msg, int payload_len)
struct scm_timestamping *tss = NULL;
struct cmsghdr *cm;
- for (cm = CMSG_FIRSTHDR(msg);
- cm && cm->cmsg_len;
- cm = CMSG_NXTHDR(msg, cm)) {
+ for_each_cmsghdr(cmsg, msg) {
if (cm->cmsg_level == SOL_SOCKET &&
cm->cmsg_type == SCM_TIMESTAMPING) {
tss = (void *) CMSG_DATA(cm);
diff --git a/crypto/af_alg.c b/crypto/af_alg.c
index 6a3ad80..3df7d53 100644
--- a/crypto/af_alg.c
+++ b/crypto/af_alg.c
@@ -399,7 +399,7 @@ int af_alg_cmsg_send(struct msghdr *msg, struct af_alg_control *con)
{
struct cmsghdr *cmsg;
- for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
+ for_each_cmsghdr(cmsg, msg) {
if (!CMSG_OK(msg, cmsg))
return -EINVAL;
if (cmsg->cmsg_level != SOL_ALG)
diff --git a/include/linux/socket.h b/include/linux/socket.h
index bb9b836..d4b592f 100644
--- a/include/linux/socket.h
+++ b/include/linux/socket.h
@@ -94,6 +94,10 @@ struct cmsghdr {
(cmsg)->cmsg_len <= (unsigned long) \
((mhdr)->msg_controllen - \
((char *)(cmsg) - (char *)(mhdr)->msg_control)))
+#define for_each_cmsg_hdr(cmsg, msg) \
+ for (cmsg = CMSG_FIRSTHDR(msg); \
+ cmsg; \
+ cmsg = CMSG_NXTHDR(msg, cmsg))
/*
* Get the next cmsg header
diff --git a/net/core/scm.c b/net/core/scm.c
index b442e7e..e938c49 100644
--- a/net/core/scm.c
+++ b/net/core/scm.c
@@ -129,8 +129,7 @@ int __scm_send(struct socket *sock, struct msghdr *msg, struct scm_cookie *p)
struct cmsghdr *cmsg;
int err;
- for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg))
- {
+ for_each_cmsghdr(cmsg, msg) {
err = -EINVAL;
/* Verify that cmsg_len is at least sizeof(struct cmsghdr) */
diff --git a/net/dccp/proto.c b/net/dccp/proto.c
index 5ab6627..d449cc5 100644
--- a/net/dccp/proto.c
+++ b/net/dccp/proto.c
@@ -703,7 +703,7 @@ EXPORT_SYMBOL_GPL(compat_dccp_getsockopt);
static int dccp_msghdr_parse(struct msghdr *msg, struct sk_buff *skb)
{
- struct cmsghdr *cmsg = CMSG_FIRSTHDR(msg);
+ struct cmsghdr *cmsg;
/*
* Assign an (opaque) qpolicy priority value to skb->priority.
@@ -717,8 +717,7 @@ static int dccp_msghdr_parse(struct msghdr *msg, struct sk_buff *skb)
*/
skb->priority = 0;
- for (; cmsg != NULL; cmsg = CMSG_NXTHDR(msg, cmsg)) {
-
+ for_each_cmsghdr(cmsg, msg) {
if (!CMSG_OK(msg, cmsg))
return -EINVAL;
diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c
index 9daf217..14a6f71 100644
--- a/net/ipv4/ip_sockglue.c
+++ b/net/ipv4/ip_sockglue.c
@@ -192,7 +192,7 @@ int ip_cmsg_send(struct net *net, struct msghdr *msg, struct ipcm_cookie *ipc,
int err, val;
struct cmsghdr *cmsg;
- for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
+ for_each_cmsghdr(cmsg, msg) {
if (!CMSG_OK(msg, cmsg))
return -EINVAL;
#if IS_ENABLED(CONFIG_IPV6)
diff --git a/net/ipv6/datagram.c b/net/ipv6/datagram.c
index 2cdc383..9895b98 100644
--- a/net/ipv6/datagram.c
+++ b/net/ipv6/datagram.c
@@ -640,7 +640,7 @@ int ip6_datagram_send_ctl(struct net *net, struct sock *sk,
int len;
int err = 0;
- for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
+ for_each_cmsghdr(cmsg, msg) {
int addr_type;
if (!CMSG_OK(msg, cmsg)) {
diff --git a/net/iucv/af_iucv.c b/net/iucv/af_iucv.c
index a089b6b..eae4e08 100644
--- a/net/iucv/af_iucv.c
+++ b/net/iucv/af_iucv.c
@@ -1070,9 +1070,7 @@ static int iucv_sock_sendmsg(struct kiocb *iocb, struct socket *sock,
txmsg.class = 0;
/* iterate over control messages */
- for (cmsg = CMSG_FIRSTHDR(msg); cmsg;
- cmsg = CMSG_NXTHDR(msg, cmsg)) {
-
+ for_each_cmsghdr(cmsg, msg) {
if (!CMSG_OK(msg, cmsg)) {
err = -EINVAL;
goto out;
diff --git a/net/rds/send.c b/net/rds/send.c
index 0a64541..1accb3e 100644
--- a/net/rds/send.c
+++ b/net/rds/send.c
@@ -826,7 +826,7 @@ static int rds_rm_size(struct msghdr *msg, int data_len)
int cmsg_groups = 0;
int retval;
- for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
+ for_each_cmsghdr(cmsg, msg) {
if (!CMSG_OK(msg, cmsg))
return -EINVAL;
@@ -878,7 +878,7 @@ static int rds_cmsg_send(struct rds_sock *rs, struct rds_message *rm,
struct cmsghdr *cmsg;
int ret = 0;
- for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
+ for_each_cmsghdr(cmsg, msg) {
if (!CMSG_OK(msg, cmsg))
return -EINVAL;
diff --git a/net/rxrpc/ar-output.c b/net/rxrpc/ar-output.c
index 0b4b9a7..f915e7e 100644
--- a/net/rxrpc/ar-output.c
+++ b/net/rxrpc/ar-output.c
@@ -45,7 +45,7 @@ static int rxrpc_sendmsg_cmsg(struct rxrpc_sock *rx, struct msghdr *msg,
if (msg->msg_controllen == 0)
return -EINVAL;
- for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
+ for_each_cmsghdr(cmsg, msg) {
if (!CMSG_OK(msg, cmsg))
return -EINVAL;
diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index 634a2ab..58834d7 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -6592,8 +6592,7 @@ static int sctp_msghdr_parse(const struct msghdr *msg, sctp_cmsgs_t *cmsgs)
struct cmsghdr *cmsg;
struct msghdr *my_msg = (struct msghdr *)msg;
- for (cmsg = CMSG_FIRSTHDR(msg); cmsg != NULL;
- cmsg = CMSG_NXTHDR(my_msg, cmsg)) {
+ for_each_cmsghdr(cmsg, my_msg) {
if (!CMSG_OK(my_msg, cmsg))
return -EINVAL;
--
1.7.7
On Wed, 2014-12-10 at 09:39 +0800, Gu Zheng wrote:
> Introduce helper macro for_each_cmsghdr as a wrapper of the enumerating
> cmsghdr from msghdr, just cleanup.
Does this even compile?
So which is it?
for_each_cmsghdr
or
for_each_cmsg_hdr?
The .h #defines for_each_cmsg_hdr
but all the uses are for_each_cmsghdr
> diff --git a/Documentation/networking/timestamping/timestamping.c b/Documentation/networking/timestamping/timestamping.c
[]
> @@ -169,9 +169,7 @@ static void printpacket(struct msghdr *msg, int res,
> res,
> inet_ntoa(from_addr->sin_addr),
> msg->msg_controllen);
> - for (cmsg = CMSG_FIRSTHDR(msg);
> - cmsg;
> - cmsg = CMSG_NXTHDR(msg, cmsg)) {
> + for_each_cmsghdr(cmsg, msg) {
> printf(" cmsg len %zu: ", cmsg->cmsg_len);
> switch (cmsg->cmsg_level) {
> case SOL_SOCKET:
> diff --git a/crypto/af_alg.c b/crypto/af_alg.c
[]
> @@ -399,7 +399,7 @@ int af_alg_cmsg_send(struct msghdr *msg, struct af_alg_control *con)
> {
> struct cmsghdr *cmsg;
>
> - for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
> + for_each_cmsghdr(cmsg, msg) {
> if (!CMSG_OK(msg, cmsg))
> return -EINVAL;
> if (cmsg->cmsg_level != SOL_ALG)
> diff --git a/include/linux/socket.h b/include/linux/socket.h
[]
> @@ -94,6 +94,10 @@ struct cmsghdr {
> (cmsg)->cmsg_len <= (unsigned long) \
> ((mhdr)->msg_controllen - \
> ((char *)(cmsg) - (char *)(mhdr)->msg_control)))
> +#define for_each_cmsg_hdr(cmsg, msg) \
> + for (cmsg = CMSG_FIRSTHDR(msg); \
> + cmsg; \
> + cmsg = CMSG_NXTHDR(msg, cmsg))
There's a mistake in this patch, please ignore it.
Sorry for the noise.
Regards,
Gu
On 12/10/2014 09:39 AM, Gu Zheng wrote:
> Introduce helper macro for_each_cmsghdr as a wrapper of the enumerating
> cmsghdr from msghdr, just cleanup.
>
>
> Signed-off-by: Gu Zheng <[email protected]>
> ---
> v2: use the lower-case macro name as Joe suggested.
> ---
> .../networking/timestamping/timestamping.c | 4 +---
> .../networking/timestamping/txtimestamp.c | 4 +---
> crypto/af_alg.c | 2 +-
> include/linux/socket.h | 4 ++++
> net/core/scm.c | 3 +--
> net/dccp/proto.c | 5 ++---
> net/ipv4/ip_sockglue.c | 2 +-
> net/ipv6/datagram.c | 2 +-
> net/iucv/af_iucv.c | 4 +---
> net/rds/send.c | 4 ++--
> net/rxrpc/ar-output.c | 2 +-
> net/sctp/socket.c | 3 +--
> 12 files changed, 17 insertions(+), 22 deletions(-)
>
> diff --git a/Documentation/networking/timestamping/timestamping.c b/Documentation/networking/timestamping/timestamping.c
> index 5cdfd74..3106e88 100644
> --- a/Documentation/networking/timestamping/timestamping.c
> +++ b/Documentation/networking/timestamping/timestamping.c
> @@ -169,9 +169,7 @@ static void printpacket(struct msghdr *msg, int res,
> res,
> inet_ntoa(from_addr->sin_addr),
> msg->msg_controllen);
> - for (cmsg = CMSG_FIRSTHDR(msg);
> - cmsg;
> - cmsg = CMSG_NXTHDR(msg, cmsg)) {
> + for_each_cmsghdr(cmsg, msg) {
> printf(" cmsg len %zu: ", cmsg->cmsg_len);
> switch (cmsg->cmsg_level) {
> case SOL_SOCKET:
> diff --git a/Documentation/networking/timestamping/txtimestamp.c b/Documentation/networking/timestamping/txtimestamp.c
> index b32fc2a..e44ef35 100644
> --- a/Documentation/networking/timestamping/txtimestamp.c
> +++ b/Documentation/networking/timestamping/txtimestamp.c
> @@ -149,9 +149,7 @@ static void __recv_errmsg_cmsg(struct msghdr *msg, int payload_len)
> struct scm_timestamping *tss = NULL;
> struct cmsghdr *cm;
>
> - for (cm = CMSG_FIRSTHDR(msg);
> - cm && cm->cmsg_len;
> - cm = CMSG_NXTHDR(msg, cm)) {
> + for_each_cmsghdr(cmsg, msg) {
> if (cm->cmsg_level == SOL_SOCKET &&
> cm->cmsg_type == SCM_TIMESTAMPING) {
> tss = (void *) CMSG_DATA(cm);
> diff --git a/crypto/af_alg.c b/crypto/af_alg.c
> index 6a3ad80..3df7d53 100644
> --- a/crypto/af_alg.c
> +++ b/crypto/af_alg.c
> @@ -399,7 +399,7 @@ int af_alg_cmsg_send(struct msghdr *msg, struct af_alg_control *con)
> {
> struct cmsghdr *cmsg;
>
> - for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
> + for_each_cmsghdr(cmsg, msg) {
> if (!CMSG_OK(msg, cmsg))
> return -EINVAL;
> if (cmsg->cmsg_level != SOL_ALG)
> diff --git a/include/linux/socket.h b/include/linux/socket.h
> index bb9b836..d4b592f 100644
> --- a/include/linux/socket.h
> +++ b/include/linux/socket.h
> @@ -94,6 +94,10 @@ struct cmsghdr {
> (cmsg)->cmsg_len <= (unsigned long) \
> ((mhdr)->msg_controllen - \
> ((char *)(cmsg) - (char *)(mhdr)->msg_control)))
> +#define for_each_cmsg_hdr(cmsg, msg) \
> + for (cmsg = CMSG_FIRSTHDR(msg); \
> + cmsg; \
> + cmsg = CMSG_NXTHDR(msg, cmsg))
>
> /*
> * Get the next cmsg header
> diff --git a/net/core/scm.c b/net/core/scm.c
> index b442e7e..e938c49 100644
> --- a/net/core/scm.c
> +++ b/net/core/scm.c
> @@ -129,8 +129,7 @@ int __scm_send(struct socket *sock, struct msghdr *msg, struct scm_cookie *p)
> struct cmsghdr *cmsg;
> int err;
>
> - for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg))
> - {
> + for_each_cmsghdr(cmsg, msg) {
> err = -EINVAL;
>
> /* Verify that cmsg_len is at least sizeof(struct cmsghdr) */
> diff --git a/net/dccp/proto.c b/net/dccp/proto.c
> index 5ab6627..d449cc5 100644
> --- a/net/dccp/proto.c
> +++ b/net/dccp/proto.c
> @@ -703,7 +703,7 @@ EXPORT_SYMBOL_GPL(compat_dccp_getsockopt);
>
> static int dccp_msghdr_parse(struct msghdr *msg, struct sk_buff *skb)
> {
> - struct cmsghdr *cmsg = CMSG_FIRSTHDR(msg);
> + struct cmsghdr *cmsg;
>
> /*
> * Assign an (opaque) qpolicy priority value to skb->priority.
> @@ -717,8 +717,7 @@ static int dccp_msghdr_parse(struct msghdr *msg, struct sk_buff *skb)
> */
> skb->priority = 0;
>
> - for (; cmsg != NULL; cmsg = CMSG_NXTHDR(msg, cmsg)) {
> -
> + for_each_cmsghdr(cmsg, msg) {
> if (!CMSG_OK(msg, cmsg))
> return -EINVAL;
>
> diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c
> index 9daf217..14a6f71 100644
> --- a/net/ipv4/ip_sockglue.c
> +++ b/net/ipv4/ip_sockglue.c
> @@ -192,7 +192,7 @@ int ip_cmsg_send(struct net *net, struct msghdr *msg, struct ipcm_cookie *ipc,
> int err, val;
> struct cmsghdr *cmsg;
>
> - for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
> + for_each_cmsghdr(cmsg, msg) {
> if (!CMSG_OK(msg, cmsg))
> return -EINVAL;
> #if IS_ENABLED(CONFIG_IPV6)
> diff --git a/net/ipv6/datagram.c b/net/ipv6/datagram.c
> index 2cdc383..9895b98 100644
> --- a/net/ipv6/datagram.c
> +++ b/net/ipv6/datagram.c
> @@ -640,7 +640,7 @@ int ip6_datagram_send_ctl(struct net *net, struct sock *sk,
> int len;
> int err = 0;
>
> - for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
> + for_each_cmsghdr(cmsg, msg) {
> int addr_type;
>
> if (!CMSG_OK(msg, cmsg)) {
> diff --git a/net/iucv/af_iucv.c b/net/iucv/af_iucv.c
> index a089b6b..eae4e08 100644
> --- a/net/iucv/af_iucv.c
> +++ b/net/iucv/af_iucv.c
> @@ -1070,9 +1070,7 @@ static int iucv_sock_sendmsg(struct kiocb *iocb, struct socket *sock,
> txmsg.class = 0;
>
> /* iterate over control messages */
> - for (cmsg = CMSG_FIRSTHDR(msg); cmsg;
> - cmsg = CMSG_NXTHDR(msg, cmsg)) {
> -
> + for_each_cmsghdr(cmsg, msg) {
> if (!CMSG_OK(msg, cmsg)) {
> err = -EINVAL;
> goto out;
> diff --git a/net/rds/send.c b/net/rds/send.c
> index 0a64541..1accb3e 100644
> --- a/net/rds/send.c
> +++ b/net/rds/send.c
> @@ -826,7 +826,7 @@ static int rds_rm_size(struct msghdr *msg, int data_len)
> int cmsg_groups = 0;
> int retval;
>
> - for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
> + for_each_cmsghdr(cmsg, msg) {
> if (!CMSG_OK(msg, cmsg))
> return -EINVAL;
>
> @@ -878,7 +878,7 @@ static int rds_cmsg_send(struct rds_sock *rs, struct rds_message *rm,
> struct cmsghdr *cmsg;
> int ret = 0;
>
> - for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
> + for_each_cmsghdr(cmsg, msg) {
> if (!CMSG_OK(msg, cmsg))
> return -EINVAL;
>
> diff --git a/net/rxrpc/ar-output.c b/net/rxrpc/ar-output.c
> index 0b4b9a7..f915e7e 100644
> --- a/net/rxrpc/ar-output.c
> +++ b/net/rxrpc/ar-output.c
> @@ -45,7 +45,7 @@ static int rxrpc_sendmsg_cmsg(struct rxrpc_sock *rx, struct msghdr *msg,
> if (msg->msg_controllen == 0)
> return -EINVAL;
>
> - for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
> + for_each_cmsghdr(cmsg, msg) {
> if (!CMSG_OK(msg, cmsg))
> return -EINVAL;
>
> diff --git a/net/sctp/socket.c b/net/sctp/socket.c
> index 634a2ab..58834d7 100644
> --- a/net/sctp/socket.c
> +++ b/net/sctp/socket.c
> @@ -6592,8 +6592,7 @@ static int sctp_msghdr_parse(const struct msghdr *msg, sctp_cmsgs_t *cmsgs)
> struct cmsghdr *cmsg;
> struct msghdr *my_msg = (struct msghdr *)msg;
>
> - for (cmsg = CMSG_FIRSTHDR(msg); cmsg != NULL;
> - cmsg = CMSG_NXTHDR(my_msg, cmsg)) {
> + for_each_cmsghdr(cmsg, my_msg) {
> if (!CMSG_OK(my_msg, cmsg))
> return -EINVAL;
>
Hi Joe,
On 12/10/2014 10:01 AM, Joe Perches wrote:
> On Wed, 2014-12-10 at 09:39 +0800, Gu Zheng wrote:
>> Introduce helper macro for_each_cmsghdr as a wrapper of the enumerating
>> cmsghdr from msghdr, just cleanup.
>
> Does this even compile?
>
> So which is it?
>
> for_each_cmsghdr
> or
> for_each_cmsg_hdr?
>
> The .h #defines for_each_cmsg_hdr
> but all the uses are for_each_cmsghdr
Thanks for your quick feedback.
There seems some problems with my send-patch script, it sent out the patch
before the test completed.
Thanks,
Gu
>
>> diff --git a/Documentation/networking/timestamping/timestamping.c b/Documentation/networking/timestamping/timestamping.c
> []
>> @@ -169,9 +169,7 @@ static void printpacket(struct msghdr *msg, int res,
>> res,
>> inet_ntoa(from_addr->sin_addr),
>> msg->msg_controllen);
>> - for (cmsg = CMSG_FIRSTHDR(msg);
>> - cmsg;
>> - cmsg = CMSG_NXTHDR(msg, cmsg)) {
>> + for_each_cmsghdr(cmsg, msg) {
>> printf(" cmsg len %zu: ", cmsg->cmsg_len);
>> switch (cmsg->cmsg_level) {
>> case SOL_SOCKET:
>> diff --git a/crypto/af_alg.c b/crypto/af_alg.c
> []
>> @@ -399,7 +399,7 @@ int af_alg_cmsg_send(struct msghdr *msg, struct af_alg_control *con)
>> {
>> struct cmsghdr *cmsg;
>>
>> - for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
>> + for_each_cmsghdr(cmsg, msg) {
>> if (!CMSG_OK(msg, cmsg))
>> return -EINVAL;
>> if (cmsg->cmsg_level != SOL_ALG)
>> diff --git a/include/linux/socket.h b/include/linux/socket.h
> []
>> @@ -94,6 +94,10 @@ struct cmsghdr {
>> (cmsg)->cmsg_len <= (unsigned long) \
>> ((mhdr)->msg_controllen - \
>> ((char *)(cmsg) - (char *)(mhdr)->msg_control)))
>> +#define for_each_cmsg_hdr(cmsg, msg) \
>> + for (cmsg = CMSG_FIRSTHDR(msg); \
>> + cmsg; \
>> + cmsg = CMSG_NXTHDR(msg, cmsg))
>
>
>
> .
>